The invention relates to telecommunication intelligent network protocols and more particularly to a finite state machine providing such intelligent network protocols.
An Intelligent Network utilizes a set of call-handling and call-routing features to provide the building blocks to create services customized to the needs of subscribersxe2x80x94business organizations, government agencies and individual end users. Some of the popular IN services are Advanced FreePhone (customers call service subscribers at specified xe2x80x9c1-800xe2x80x9d numbers free of charge), Universal Number (service subscribers can advertise a single telephone number for callers to dial from any location in the country), Virtual Private Network (the same functions available through private networks are offered using facilities of the PSTNxe2x80x94Public Switched Telephone Network), Televoting (subscribers can survey public opinion using the PSTN), Calling Card (customers can place calls from any standard telephone to any destination with costs charged to the account specified by the calling card number) and Personal Number (remote call forwarding for subscribers who move frequently among locations).
There are five network elements that constitute an Intelligent Network:
The Service Control Point (SCP)
The SCP is the core of the IN. It contains the centralized database that stores service subscriber profiles, service information and call processing information.
The Service Switching Point (SSP)
The SSP recognizes an incoming IN call and xe2x80x9cqueriesxe2x80x9d the SCP for further instructions. The SSP then provides network switching functionality, based on the instructions received from the SCP.
The Intelligent Peripheral (IP)
The IP offers capabilities such as customized recorded announcements, digit collection and speech recognition. The IP can be integrated within the SSP or it can be standalone, i.e. external to the SSP.
The Service Management System (SMS)
The SMS gives network providers and service subscribers access to the Service Control Point (SCP) and also manages all intelligent network service and subscriber related data.
The Service Creation Environment (SCE)
The SCE enables network providers to create and introduce new services by building a decision tree that specifies the new service.
There are several standardization bodies for Intelligent Network‥the American National Standards Institute (ANSI), the European Telecommunication Standards Institute (ETSI) and the International Telecommunications Union (ITU, formerly known as CCITT). ANSI provides US contributions, ETSI provides contributions from Europe and from other ETSI member countries. ITU serves as the world-wide standardization body, receiving input from ANSI, ETSI and other member countries that are members of neither of these two regional bodies. ITU defines Intelligent Network standards in xe2x80x9cCapability Setsxe2x80x9d. The first approved phase of ITU IN standards was Capability Set 1, also known as CS-1. CS-1 supports a multi-vendor environment for SSP and SCP network elements.
The IN standards define an intelligent network in terms of Functional Entities (FEs) which provide certain functionality within a Physical Entity (PE). With regards to the Intelligent Network configuration shown in FIG. 1, there are three Physical Entities for which Functional Entities have been defined. These PEs are the SSP, the SCP and the IP.
The SSP Physical Entity which consists of several Functional Entities. The Call Control Function (CCF) FE provides call/service processing and control. The CCF FE establishes, manipulates and releases calls/connections. The Service Switching Function (SSF) FE, in association with the CCF FE, provides the set of functions required for interaction between the CCF FE and the Service Control Function (SCF) FE which is part of the SCP PE. The Specialized Resource Function (SRF) FE provides the specialized resources required for the execution of IN provided services (e.g. digit receivers, announcements, conference bridges, etc.). Note that the SRF FE can be integrated within the SSP PE or it can be external to the SSP PE. The SSP PE has either single interactions with other PEs, in which case the Single Association Control Function (SACF) provides a coordination-ordination function, or it has multiple coordinated interactions with other PEs, in which case the Multiple Association Control Function (MACF) provides the coordination function.
In order to communicate with the SCP, the SSP uses a protocol stack. On top of the stack is the Intelligent Network Application Protocol (INAP) which is the application or user part. This is the protocol that is used to define IN services. INAP utilizes the Transaction Capabilities Application Part (TCAP), which is the protocol that provides the capability to exchange messages between the SSP and the SCP. This message exchange between SSP and SCP is called a TCAP Dialogue. TCAP, in turn, lies on top of the Signaling Connection Control Part (SCCP) which is the protocol employed for addressing the Physical Entity with which a dialogue is required. Finally, SCCP uses the Message Transfer Part (MTP) which is responsible for the physical connections between Physical Entities.
As mentioned previously, the user protocol for communication between the SSP and the SCP for Intelligent Network calls is the Intelligent Network Application Protocol (INAP). ETSI has defined its version of the ITU INAP Capability Set 1 in its European Telecommunication Standard (ETS) 300 374-1 document.
Thus, there is a need in the art to provide an implementation of the INAP protocol, also known as ETSI INAP for a 5ESS-2000(copyright) switch in an SSP offering for the Intelligent Network. 5ESS and 5ESS-2000 are trademarks of Lucent Technologies Inc.
Briefly stated in accordance with one aspect of the invention, the aforementioned need is provided by a finite state machine implementation of the ETSI INAP protocol, especially an implementation on the 5ESS-2000 SSP.
In accordance with one aspect of the invention, the aforementioned need is fulfilled by a finite state machine that provides ETSI INAP capability set 1 intelligent network application protocol which includes a first finite state machine and a second finite state machine connected to said first finite state machine.
In accordance with a specific embodiment of the invention, the aforementioned need is fulfilled by a finite state machine that provides ETSI INAP capability set 1 intelligent network application protocol which includes a first finite state machine and a second finite state machine connected to said first finite state machine. The first finite state machine provides each transition between states in response to input data. After the first finite state machine has provided a transition to a state, the second finite state machine is given control and determines if the state to which the first finite state machine has transitioned is the appropriate state and causes the first finite state machine to transition to the appropriate state if the first finite state machine had previously transitioned to a state other than the appropriate state.